CN102249538A

CN102249538A - Optical glass, preform for precision press molding, optical element, methods for manufacturing the same, and image pickup device

Info

Publication number: CN102249538A
Application number: CN2011100784388A
Authority: CN
Inventors: 高泽洋树
Original assignee: Hoya Corp
Current assignee: Hoya Corp
Priority date: 2010-03-31
Filing date: 2011-03-30
Publication date: 2011-11-23
Anticipated expiration: 2031-03-30
Also published as: JP2011213554A; EP2374764B1; US8647996B2; CN102249538B; EP2374764A1; US20110245063A1; JP5813926B2

Abstract

The present invention relates to an optical glass, a preform for precision press molding, methods for manufacturing the same, and an image pickup device. The optical glass of the present invention not only has a high refractive index, a high dispersion property, and good precision press moldability, but also has good stability with respect to devitrification when reheated (referred to as "devitrification stability upon reheating"), and is an optical glass with a good partial dispersion ratio (Pg, F).

Description

Opticglass, precise compression molding are with pre-type body, optical element, their manufacture method and camera head

Technical field

The present invention relates to opticglass, precise compression molding with pre-type body, optical element, their manufacture method and camera head.Opticglass of the present invention has the high dispersion property of high refractive index, has excellent precise compression molding, and during reheat for the stability of devitrification (below, anti-devitrification stability when being sometimes referred to as reheat) excellence, and local disperse than (relative partial dispersion (partial dispersion ratio)) (Pg, F) also excellent.

Background technology

The demand that high refractivity high dispersion is learned glass is very high, lens of using as high performance digital camera particularly, and the non-spherical lens that is formed by above-mentioned glass is indispensable.

As the method for volume production non-spherical lens, precise compression molding method (being also referred to as mould optical mode platen press (モ one Le De オプテイ Network スプレス method (mold optics pressing method))) is well-known.Learn glass as the high refractivity high dispersion that can utilize the moulding of precise compression molding method, phosphate-based glass is well-known.Though phosphate-based opticglass is very good glass, the problem that glass surface sustains damage easily when having precise compression molding.

High refractivity high dispersion as nonphosphate system is learned glass, and disclosed glass is well-known in the patent documentation 1～5.The composition of these glass is silica-based composition.

The prior art document

Patent documentation

Patent documentation 1:W02004/110942

Patent documentation 2: TOHKEMY 2004-161598 communique

Patent documentation 3: TOHKEMY 2002-87841 communique

Patent documentation 4: TOHKEMY 2009-179522 communique

Patent documentation 5: TOHKEMY 2009-179538 communique

Summary of the invention

Learn glass in order to obtain high refractivity high dispersion, no matter phosphate-based, silica-based, all need to introduce the composition that Nb, Ti etc. are used to give the high chromatic dispersion of high refractive index.

Yet if will contain the glass precise compression molding of Nb, Ti etc., redox reaction can take place in the interface between glass and the compression molding mould, and its result produces foaming at lens surface, can be difficult to keep the problem of the high-caliber rate that manufactures a finished product.This problem is obvious when the compression molding temperature is higher, but with phosphate-based glassy phase ratio, the second-order transition temperature of silica-based glass is higher, must improve the compression molding temperature, thus the reaction between glass and the compression molding mould when having encouraged precise compression molding.

For example, the second-order transition temperature of disclosed glass is more than 540 ℃ in the patent documentation 1, therefore has the problem that can not suppress above-mentioned reaction because second-order transition temperature is too high.

Disclosed glass and patent documentation 1 exist equally that stability, glass is low, the problem of easy devitrification in the patent documentation 2.Particularly, the specific refractory power of patent documentation 2 described glass is more than 1.88, contains the composition Ti of a large amount of raising glass refractions in this glass ⁴⁺, Nb ⁵⁺, W ⁶⁺, Ba ²⁺, Ca ²⁺, Zr ⁴⁺And Li ⁺

A kind of middle specific refractory power high-dispersion glass (claim 1) and high refractive index high-dispersion glass (claim 2) are disclosed in the patent documentation 3.Patent documentation 3 described high refractive index high-dispersion glasses contain a large amount of SiO ₂And TiO ₂, SiO ₂Has the effect that improves second-order transition temperature, TiO ₂When precise compression molding, be easy to and be molded into the profile reaction.Therefore, there is following problem: if rising, second-order transition temperature then must improve the compression molding temperature, thus the reaction between glass and the compression molding mould when having encouraged precise compression molding.The problem that exist the thermostability of glass low in addition, liquidus temperature is high.

Disclose in the patent documentation 4 and a kind ofly had high refractive index and high dispersion property, keep low local the dispersion simultaneously than (Pg, opticglass F).The glass of patent documentation 4 disperses than (Pg F) has adjusted Nb in order to suppress local ₂O ₅And TiO ₂Ratio.But there is the high problem of liquidus temperature in patent documentation 4 described glass.The formability of liquidus temperature and glass is closely related, if too high brush line or the component fluctuation that then is easy to generate glass ingredient of liquidus temperature.If in order to suppress this problem with low temperature moulding, the problem that then exist viscosity to reduce, to be difficult to moulding.

Also disclose in the patent documentation 5 and a kind ofly had high refractive index and high dispersion property, keep low local the dispersion simultaneously than (Pg, opticglass F).The glass of patent documentation 5 is in order to keep low local the dispersion than (Pg F) makes Nb ₂O ₅Content surpass 40 quality %.But also there is the high problem of liquidus temperature in patent documentation 5 described glass.The formability of liquidus temperature and glass is closely related.If liquidus temperature is too high, then be easy to generate the brush line or the component fluctuation of glass ingredient.If in order to suppress this problem with low temperature moulding, the problem that then exist viscosity to reduce, to be difficult to moulding.In addition because TiO ₂, Nb ₂O ₅And ZrO ₂Total content many, thermostability is low, can produce crystal during the stirred glass liquation for the opticglass that obtains homogeneous separates out, perhaps separate out etc. glass melt being poured in the mold and can producing crystal during moulding, becoming very big obstacle aspect the volume production opticglass.

Under such situation, expectation realizes a kind of high refractivity high dispersion glass that can pass through the high-quality optical element of precise compression molding stably manufactured, the part that described opticglass can keep lower disperses than (Pg F), and can suppress liquidus temperature.

The invention solves the problems referred to above, when purpose is to provide a kind of reheat for the excellent in stability of devitrification and have low local disperse than (Pg, high refractivity high dispersion F), the precise compression molding excellence is learned glass; Provide the precise compression molding that forms by above-mentioned opticglass with pre-type body and optical element; The camera head that their manufacture method is provided and possesses above-mentioned optical element.

The present invention is as described below.

[1]

A kind of opticglass, it is an oxide glass, when representing with positively charged ion %, it contains:

15%～35% Si ⁴⁺,

0%～20% B ³⁺,

15%～25% Nb ⁵⁺,

0%～9% Ti ⁴⁺,

0%～3% Zr ⁴⁺,

025%～2.5% W ⁶⁺,

0%～19% Li ⁺,

3%～19% Na ⁺,

0%～18% K ⁺,

0%～9% Zn ²⁺,

0%～2% Ba ²⁺With

0%～3% Ca ²⁺,

Nb ⁵⁺Content with respect to Nb ⁵⁺And Ti ⁴⁺The cation ratio (Nb of total content ⁵⁺/ (Nb ⁵⁺+ Ti ⁴⁺)) be 0.71～1 scope,

With Si ⁴⁺Measure and Nb for 20 times of content ⁵⁺Total (the 20Si of 2 times of amounts of content ⁴⁺+ 2Nb ⁵⁺) be made as H, with B ³⁺8 times of amounts of content, Li ⁺6 times of amounts of content, Na ⁺5 times of amounts of content, K ⁺3 times of amounts of content, Zn ⁺Measure and W for 3 times of content ⁶⁺Total (the 8B of 7 times of amounts of content ³⁺+ 6Li ⁺+ 5Na ⁺+ 3K ⁺+ 3Zn ²⁺+ 7W ⁶⁺) when being made as L, H/L is 1.15～2.55 scope,

Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺Total content be 20%～30.78% scope,

Ba ²⁺, Ca ²⁺And Zr ⁴⁺Total content be 0%～3.79% scope,

Ti ⁴⁺, Nb ⁵⁺, W ⁶⁺, Ba ²⁺, Ca ²⁺, Zr ⁴⁺And Li ⁺Total content be below 50%,

Refractive index n d is 1.75～1.86 scope,

Abb vd is 24～30 scope.

[2]

As [1] described opticglass, wherein, second-order transition temperature is 480 ℃～535 ℃ a scope.

[3]

As [1] or [2] described opticglass, wherein, liquidus temperature is 1000 ℃～1060 ℃ a scope.

[4]

As each described opticglass of [1]～[3], wherein, (Pg is 0.57～0.62 F) than (relative partial dispersion (partialdispersion ratio)) in local dispersion.

[5]

As each described opticglass of [1]～[4], wherein, Si ⁴⁺And B ³⁺Total content be 20%～50%.

[6]

As each described opticglass of [1]～[5], wherein, Sr ²⁺Content be 0%～2% scope.

[7]

As each described opticglass of [1]～[6], wherein, Ba ²⁺And Ca ²⁺Total content be 0%～3% scope.

[8]

As each described opticglass of [1]～[7], wherein, Li ⁺, Na ⁺And K ⁺Total content be 25%～45% scope.

[9]

A kind of precise compression molding forms with pre-type body, its each described opticglass by [1]～[8].

[10]

A kind of precise compression molding is made as [9] described pre-type bodies (preform) via following operation of the manufacture method of pre-type body: melten glass is made in frit heating, fusion, and made described melten glass moulding.

[11]

A kind of optical element, its each described opticglass by [1]～[8] forms.

[12]

A kind of manufacture method of optical element, described manufacture method possesses following operation: [9] described precise compression molding is heated with pre-type body, use compression molding mould (precision press molding) to carry out precise compression molding (precision press molding).

[13]

As the manufacture method of [12] described optical element, wherein, precise compression molding is heated in the lump with pre-type body and compression molding mould, carry out precise compression molding.

[14]

As the manufacture method of [12] described optical element, wherein, after the heating precise compression molding is with pre-type body, import in the compression molding mould after the preheating, carry out precise compression molding.

[15]

A kind of camera head, it possesses [11] described optical element.

When the invention provides a kind of reheat for the excellent in stability of devitrification and have low local the dispersion than (Pg, high refractivity high dispersion F), the precise compression molding excellence is learned glass.Provide the precise compression molding that forms by above-mentioned opticglass with pre-type body and optical element, their manufacture method and the camera head that possesses above-mentioned optical element in addition.

Description of drawings

Fig. 1 show in the comparative example in fusion with the photo of the material of compositions glass melt state devitrification, patent documentation 5 embodiment 40.

Embodiment

Below, describe opticglass of the present invention in detail, below unless otherwise specified, then the content of each cation constituent, total content are represented with positively charged ion %.

Si ⁴⁺, B ³⁺Be that glass network forms oxide compound (glass network-forming oxide), aspect the formability of keeping stability, glass, melten glass be necessary composition.

Si ⁴⁺Except above-mentioned effect, also have the effect of the phase-splitting when suppressing precise compression molding, have the effect that improves chemical durability, the reduction of the viscosity when suppressing the melten glass moulding, keeps the state that is suitable for moulding simultaneously.But excessive introducing can cause second-order transition temperature, liquidus temperature to rise, and meltbility, devitrification resistance reduce.By suppressing phase-splitting, can prevent glass that gonorrhoeaization produced was loss of transmission.From this point of view, Si ⁴⁺Content range be 15%～35%, preferred range is 16%～32%, preferred scope is 17%～30%, further preferred range is 18%～29%.

B ³⁺Except above-mentioned effect, also have and improve meltbility, reduce the effect of second-order transition temperature simultaneously, but excessive introducing can cause chemical durability to reduce.By improving meltbility, even glass melting temperature height also can access the glass of homogeneous.Its result can also suppress the erosion of crucible, and the materials such as platinum that can suppress to constitute crucible fuse into the painted of the caused glass of glass.From this point of view, B ³⁺Content range be 0%～20%, preferred range is 1%～19%, preferred scope is 2%～18%, further preferred range is 3%～17%, the scope that is more preferably is 4%～16%, further preferred range is 5%～15%.

If the excessive Si that contains ⁴⁺And B ³⁺, then specific refractory power reduces, so Si ⁴⁺And B ³⁺The preferable range of total content be 20%～50%.Si ⁴⁺And B ³⁺The preferable range of total content be 20%～45%, preferred scope is 21%～44%, further preferred range is 22%～43%, the scope that is more preferably is 28%～40%.

Nb ⁵⁺, Ti ⁴⁺, W ⁶⁺And Zr ⁴⁺All are compositions that high refractive index, high chromatic dispersionization are had very big effect.

Nb ⁵⁺Except above-mentioned effect, also has the effect that improves devitrification resistance, reduces liquidus temperature.In addition, it has makes local dispersion property near normal line (ノ one マ Le ライ Application (normal line)),, makes Δ Pg that is, and F is near zero effect, but raise devitrification resistance reduction, liquidus temperature excessive containing sometimes.From this point of view, Nb ⁵⁺Content range be set at 15%～25%.Nb ⁵⁺The preferable range of content be 16%～24%, preferred scope is 17%～23%, further preferred range is 18%～22%.

Ti ⁴⁺Except above-mentioned effect, also have the effect that improves devitrification resistance and chemical durability, but excessive containing sometimes, the phase-splitting tendency during precise compression molding can increase greatly.From this point of view, Ti ⁴⁺Content range be set at 0%～9%.Ti ⁴⁺The preferable range of content be 1.0%～9.0%, preferred scope is 1.5%～9.0%, further preferred range is 2.0%～8.5%, the scope that is more preferably is 2.5%～8.5%, further preferred range is 2.5%～8.0%, further is preferably 2.5%～7.5%.

Nb ⁵⁺Content with respect to Nb ⁵⁺And Ti ⁴⁺The cation ratio (Nb of total content ⁵⁺/ (Nb ⁵⁺+ Ti ⁴⁺)) scope be 0.71～1, in this scope, obtain local the dispersion easily than (Pg is F) at the opticglass of desired scope 0.57～0.62.Cation ratio (Nb ⁵⁺/ (Nb ⁵⁺+ Ti ⁴⁺)) preferable range be 0.72～0.95, preferred scope is 0.73～0.9, further preferred range is 0.73～0.89, the scope that is more preferably is 0.73～0.88.

Zr ⁴⁺Except above-mentioned effect, also have the phase-splitting when suppressing precise compression molding, the effect that improves chemical durability and devitrification resistance, but raise devitrification resistance reduction, liquidus temperature excessive containing sometimes.From this point of view, Zr ⁴⁺Content range be 0%～3%, preferred range is 0%～2.5%, preferred scope is 0.1%～2.0%, further preferred range is 02%～1.9%, the scope that is more preferably is 0.3%～1.8%.

W ⁶⁺Except above-mentioned effect, also have the effect that improves devitrification resistance, suppresses the liquidus temperature rising, but raise devitrification resistance deterioration, liquidus temperature excessive containing sometimes.In addition, also make painted enhanced tendency.From this point of view, W ⁶⁺Content range be 0.25%～2.5%, preferred range is 0.3%～2.5%, preferred scope is 0.4%～2.3%, further preferred range is 0.5%～2.0%, the scope that is more preferably is 0.5%～1.65%.

Li ⁺, Na ⁺, K ⁺Be to have the composition that improves meltbility, reduces the effect of second-order transition temperature.

Li ⁺Be in alkali metal component, to keep high refractive index, reduce the composition of the effect maximum of second-order transition temperature simultaneously, but excessive containing sometimes, make that stability, glass reduces, liquidus temperature raises.From this point of view, Li ⁺The scope of content be set at 0%～19%, preferred range is 5%～18%, preferred scope is 6%～19%, further preferred range is 7%～18%, the scope that is more preferably is 10%～17%.

Na ⁺, K ⁺Except above-mentioned effect, by with Li ⁺Coexistence utilizes mixed alkali effect and has the effect of further raising stability, glass.From this point of view, Na ⁺Content range be set at 3%～19%, preferred range is 5%～18%, preferred scope is 7%～19%, further preferred range is 8%～18%, the scope that is more preferably is 10%～17%.Equally, K ⁺Content range be set at 0%～18%, preferred range is 1%～17%, preferred scope is 1%～16%, further preferred range be 1%～15%, be more preferably 1%～14%, further preferred range is 1%～13%, further preferred range is 2%～12%.

Zn ²⁺, Ba ²⁺, Sr ²⁺, Ca ²⁺Useful in the adjustment of optical constant, these compositions can improve meltbility and transmittance, and join in the frit by the form with carbonate, nitrate, can improve clarifying effect.

Ba ²⁺Except above-mentioned effect, also has the effect that improves specific refractory power, the phase-splitting when suppressing precise compression molding simultaneously.But, excessive containing sometimes, have the tendency that the devitrification resistance of making reduces, liquidus temperature raises, chemical durability reduces.From this point of view, Ba ²⁺Content range be 0%～2%, Ba ²⁺The preferable range of content be 0.1%～2%, preferred scope is 02%～1.9%, further preferred range is 0.3%～1.8%, the scope that is more preferably is 0.4%～1.7%, further preferred range is 0.5%～1.6%.

Zn ²⁺Except above-mentioned effect, the effect that reduces second-order transition temperature is also excellent, the effect that also has the high refractive index kept.But, excessive containing sometimes, have the tendency that the devitrification resistance of making reduces, liquidus temperature rises, chemical durability reduces.Zn ²⁺The preferable range of content be 0%～9%, preferred scope is 0%～5%, further preferred range is 0%～4%, the scope that is more preferably is 0%～3%, further preferred range is 0%～2%.

Sr ²⁺Except above-mentioned effect, though compare Ba ²⁺Effect little, but have the effect that improves specific refractory power.In addition, the effect that also has the phase-splitting when suppressing precise compression molding.But, excessive containing sometimes, have the tendency that the devitrification resistance of making reduces, liquidus temperature rises, chemical durability reduces.Sr ²⁺The preferable range of content be 0%～2%, preferred scope is 0%～1.5%, further preferred range is 0%～1%.

Ca ²⁺Except above-mentioned effect, also has the effect of the phase-splitting when suppressing precise compression molding.But, excessive containing sometimes, have the tendency that the devitrification resistance of making reduces, liquidus temperature rises, second-order transition temperature rises, chemical durability reduces.Ca ²⁺The preferable range of content be 0%～3%, preferred scope is 0%～2%, further preferred range is 0%～1.5%, the scope that is more preferably is 0%～1.0%, further preferred range is 0%～0.9%.

With Si ⁴⁺Measure and Nb for 20 times of content ⁵⁺Total (the 20Si of 2 times of amounts of content ⁴⁺+ 2Nb ⁵⁺) be made as H, with B ³⁺8 times of amounts of content, Li ⁺6 times of amounts of content, Na ⁺5 times of amounts of content, K ⁺3 times of amounts of content, Zn ⁺Measure and W for 3 times of content ⁶⁺Total (the 8B of 7 times of amounts of content ³⁺+ 6Li ⁺+ 5Na ⁺+ 3K ⁺+ 3Zn ²⁺+ 7W ⁶⁺) when being made as L, H/L is 115～2.55 scope.Si ⁴⁺And Nb ⁵⁺Be high Tg composition, that is, if increase the content of these compositions, then glass transition temperature Tg rises, on the other hand, and B ³⁺, Li ⁺, Na ⁺, K ⁺, Zn ²⁺And W ⁶⁺Be low Tg composition, that is, if increase the content of these compositions, then glass transition temperature Tg descends.The appended coefficient of each composition is represented the variation of the glass transition temperature Tg that increment produced of a kind of positively charged ion %.Below, this point is described in detail.

The variation of the glass transition temperature Tg that increment produced of the per 1 positively charged ion % of each composition has been shown in the table 1.The index of Δ Tg in each composition obtains by chemical experiment.

Table 1

Each composition of table 1 is to the influence of Tg

Composition	ΔTg
		Li	-6
Na	-5
		K	-3
B	-8
		Zn	-3
Nb	+2
		W	-7
Si	+20

With the composition enumerated in the table 1 according to the index of Δ Tg for just (H) with for negative (L) divides into groups, the coefficient shown in the table 1 be multiply by the content of each composition that positively charged ion % represents, represent that with summation the index of Δ Tg is that the summation H of positive composition can be designated as 20Si ⁴⁺+ 2Nb ⁵⁺, the index of Δ Tg can be designated as 8B for the summation L of negative composition ³⁺+ 6Li ⁺+ 5Na ⁺+ 3K ⁺+ 3Zn ²⁺+ 7W ⁶⁺And the value of H is big more, and then the Tg that shows of glass is high relatively more, and the L value is big more, and then the Tg that shows of glass is low relatively more.H/L is the relative index of the Tg that shows of glass, in order to obtain the lower glass of Tg, then need keep lower H/L.In the present invention, consider that from the aspect of opticglass that obtains Tg is adjusted at 480～535 ℃ scope H/L is 1.15～2.55 scope.If H/L is lower than 1.15, then the index of Δ Tg is excessive for the summation of negative composition, and the Tg of glass is lower than 480 ℃ through regular meeting.If second-order transition temperature is too low, then thermostability reduces, and therefore wishes to make second-order transition temperature and thermostability balance.On the other hand, if H/L surpasses 2.55, then the index of Δ Tg is that the summation of positive composition is excessive, second-order transition temperature through regular meeting above 535 ℃.The preferable range of H/L is 1.15～2.55, preferred scope is 1.20～2.55, further preferred range is 1.25～2.55, the scope that is more preferably is 1.27～2.55, further preferred range is 1.30～2.55.

For patent documentation 1 described opticglass, obtain above-mentioned H/L, the result is 2.80～3.98 scope, this with second-order transition temperature up to conforming to more than 540 ℃.

Just, the Tg of glass and not only by the H/L decision also changes for positive composition with for the ratio of the total content of negative composition with the total content of in addition composition according to the index of above-mentioned Δ Tg.And, among the present invention,, so to consider that also characteristic except that Tg decides the composition of glass because characteristic except that Tg is also in desired scope.

If Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺Total content be lower than 20%, then be difficult to when keeping the thermostability of glass, realize needed optical characteristics.On the other hand, if Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺Total content more than 30.78%, then the thermostability of glass significantly reduces, and also is easy to generate crystal during reheat and separates out.In addition, liquidus temperature also raises, and is difficult to mold high-quality glass material.Reason according to such makes Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺Total content (Ti ⁴⁺+ Nb ⁵⁺+ Zr ⁴⁺) be 20%～30.78%.Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺The preferred range of total content be 24%～29.9%.

If Ba ²⁺, Ca ²⁺And Zr ⁴⁺Total content surpass 3.79%, then the thermostability of glass sharply reduces, and also is easy to generate crystal during reheat and separates out.In addition, liquidus temperature and second-order transition temperature raise, and are difficult to mold high-quality glass material, perhaps compression molding deterioration.Therefore, make Ba ²⁺, Ca ²⁺And Zr ⁴⁺Total content be 0%～3.79%.The preferred scope of the total content of mentioned component is 0.5%～3.75%, further preferred range is 0.8%～3.70%.

Ba ²⁺And Ca ²⁺Total content be preferably 0%～3% scope.If Ba ²⁺And Ca ²⁺Total content surpass 3%, then the thermostability of glass sharply reduces, and also is easy to generate crystal during reheat and separates out.In addition, liquidus temperature and second-order transition temperature raise, and are difficult to the high-quality glass material of moulding, perhaps compression molding deterioration.Ba ²⁺And Ca ²⁺The preferred scope of total content be 0.5%～2.8%, further preferred range is 0.8%～2.5%.

Ti ⁴⁺, Nb ⁵⁺, W ⁶⁺, Ba ²⁺, Ca ²⁺, Zr ⁴⁺And Li ⁺Total content be below 50%.As mentioned above, Nb ⁵⁺, Ti ⁴⁺, W ⁶⁺And Zr ⁴⁺All are compositions that the high chromatic dispersionization of high refractive index is had very big effect.In addition, Ba ²⁺And Ca ²⁺Still improve the composition of specific refractory power among the alkaline-earth metal, Li ⁺Still keep the composition of high refractive index in the alkali metal component.Opticglass of the present invention has than higher specific refractory power, and refractive index n d is 1.75～1.86 scope, is below 50% by the total content that makes mentioned component, can realize the refractive index n d of this scope.The preferable range of the total content of mentioned component is 30%～50%, preferred scope is 32%～50%, further preferred range is 42%～50%, the scope that is more preferably is 40%～49%, further preferred range is 42%～48%.

La ³⁺, Gd ³⁺, Y ³⁺, Yb ³⁺Except having the effect that makes the low chromatic dispersionization of glass, also have the effect that improves second-order transition temperature Deng the rare earth class composition, the total content that therefore preferably makes the rare earth class composition is 0%～1.5% scope.The preferable range of the total content of rare earth class composition is 0%～1%, preferred scope is 0%～0.5%.Yet, further preferred rear earth containing composition not.

Ge ⁴⁺Be extremely expensive composition, even do not use Ge ⁴⁺Therefore also can reach needed purpose, preferably making its content is 0%～1% scope, 0%～0.5% scope more preferably, however further preferably do not contain Ge ⁴⁺

Consider from environment being produced dysgenic aspect, preferably do not introduce Pb, Te, Cd, Cr, As glass ingredient or additive.Cu, Co, Eu, Er, Nd, Pr, Tb, Fe have the effect of the glass coloring of making, and therefore preferably are not incorporated in the glass.

Need to prove, consider Si from the aspect that reaches purpose of the present invention ⁴⁺, B ³⁺, Nb ⁵⁺, Ti ⁴⁺, Zr ⁴⁺, W ⁶⁺, Li ⁺, Na ⁺, K ⁺, Ba ²⁺, Ca ²⁺And Zn ²⁺Total content be preferably more than 95%, more preferably more than 97%, more preferably more than 98%, be more preferably more than 99%, be preferably 100% especially.

Be scaled oxide compound and when representing (cutting り In (based on the totalamount of the galss components) outward) with respect to the ratio of glass ingredient total amount, can add the Sb of 0%～2 quality % in the opticglass of the present invention ₂O ₃, 0%～2 quality % SnO ₂These additives can also Sb except can be used as finings performance function ₂O ₃Can also suppress the painted of glass that sneaking into of impurity such as Fe produced.To represent Sb with respect to the ratio of glass ingredient total amount ₂O ₃, SnO ₂Addition be preferably 0%～1 quality %, 0%～0.5 quality % more preferably respectively.

Opticglass of the present invention is oxide glass, and in anionic component, 50 negatively charged ion % are above to be O ^2-In addition, can also introduce a spot of F ^-, Cl ^-, I ^-, Br ^-O ^2-The preferable range of content be 50～100 negatively charged ion %, preferred scope be 80～100 negatively charged ion %, more preferably 85～100 negatively charged ion %, be more preferably 90～100 negatively charged ion %, further be preferably 95～100%, further be preferably 98～100 negatively charged ion %, further be preferably 99～100 negatively charged ion %, be preferably 100 negatively charged ion % especially.

[specific refractory power, Abb]

The refractive index n d of opticglass of the present invention is 1.75～1.86 scope, and Abb vd is 24～30 scope.The opticglass of the material by making refractive index n d in above-mentioned scope, can access the optical element that is suitable for constituting high function, small-sized optical system.Need to prove,, when making has the lens of identical focusing power, can slow down the curvature of lens face by using glass of high refractive index.Its result, the formability in the time of can also improving the lens precise compression molding.Make Abb vd can access a kind of opticglass in above-mentioned scope, this opticglass is suitable as the material of following lens: these lens can carry out excellent aberration (chromatic aberration) correction with the set of lenses that is formed by low dispersion is fashionable.

The preferable range of refractive index n d is 1.755～1.855, preferred scope is 1.756～1.854, further preferred range is 1.79～1.85, and the preferable range of Abb vd is 24.0～29.5, preferred scope is 24.2～28, further preferred range is 24.5～27.5.Specific refractory power is too high or the too little meeting of Abb vd makes stability, glass be tending towards reducing and second-order transition temperature is tending towards raising.

[second-order transition temperature]

The second-order transition temperature of opticglass of the present invention is preferably 480 ℃～535 ℃ scope, more preferably 485 ℃～530 ℃ scope, more preferably 490 ℃～530 ℃ scope.Be accompanied by the reduction of second-order transition temperature, more the compression molding temperature is set in the lowland.The surface reaction of glass and compression molding mould carries out the very big influence that speed is subjected to the height of compression molding temperature during precise compression molding.Therefore, even only make second-order transition temperature reduce several ℃ or tens ℃, also can significantly suppress surface reaction.Usually if improve specific refractory power, then second-order transition temperature demonstrates the tendency of rising, but the present invention can access glass of high refractive index, and it has the lower glass transition temperatures that is suitable for precise compression molding.

[liquidus temperature]

The liquidus temperature of opticglass of the present invention is preferably 1000 ℃～1060 ℃ scope.Preferred liquidus temperature is 1000 ℃～1055 ℃ a scope, and further preferred liquidus temperature is 1000 ℃～1050 ℃ a scope.By keeping lower liquidus temperature, the temperature in the time of can reducing the melten glass moulding.By keeping above-mentioned low mold temperature, can suppress of the surface volatilization of easy evaporable composition such as boric acid or basic metal, and can suppress the change of glass performance or the generation of surperficial brush line (table face Veins reason) from melten glass.

Usually if improve specific refractory power, then liquidus temperature demonstrates the tendency of rising, but according to the present invention, even glass of high refractive index also can access the glass of the low liquidus temperature of production excellence.Think generally speaking to be difficult to carry out simultaneously high refractive indexization, lower glass transition temperaturesization, low liquidus temperatureization, but can realize this three characteristics simultaneously according to the present invention.

[local chromatic dispersion (part dispersed (partial dispersion)) property]

In order to realize the high order aberration in image pickup optical system, projection optical system etc., it is effective being used in combination low dispersion system lens and high-dispersion glass system lens.But, the glass of low chromatic dispersion side often demonstrates bigger part and disperses ratio, therefore proofreading and correct under the situation of the aberration of high order more, and except high chromatic dispersion (high-dispersion) characteristic, also having local the dispersion than (partial dispersion ratio)) the lens combination of little glass is more effective.

The invention provides a kind of high refractivity high dispersion and learn glass, this glass has the low local ratio that disperses, and is suitable for the correction of high order aberration.

Use each refractive index n g, nF, nc in g line, F line, the c line, the part is disperseed than Pg, F is expressed as (ng-nF)/(nF-nc).Disperse than Pg in the part, among the F-Abb vd figure, will disperse than being expressed as Pg, F as the part on the normal line of the benchmark of normal local dispersive glass (normalpartial dispersion glass) ⁽⁰⁾, Pg, F ⁽⁰⁾Use Abb vd to represent with following formula.

Pg，F ⁽⁰⁾＝0.6483-(0.0018×vd)

Δ Pg, F are local the dispersions than Pg, and F and above-mentioned normolineal deviation are represented with following formula.

ΔPg，F＝Pg，F-Pg，F ⁽⁰⁾

＝Pg，F+(0.0018×vd)-0.6483

The part of opticglass of the present invention disperses than Pg, and F is preferably 0.57～0.62, more preferably 0.58～0.62, more preferably 0.59～0.62.Need to prove that the part of opticglass of the present invention disperses than Pg, the deviation delta Pg of F, F be preferably below 0.016, more preferably below 0.015, more preferably below 0.014.Be the glass that is suitable for good high order chromatic aberration correction.

Therefore though opticglass of the present invention is the high refractive index high-dispersion glass, demonstrates high transmission rate in the wide region of visibility region, is suitable as and is used for making lens, prism etc. require the optical element of high-transmission rate in visibility region glass material.The preferable range of degree of staining λ 80 is that 515nm is following, preferred scope is below the 505nm.Spectral transmission in the wave band of λ 80～700nm is shown as more than 80%.The preferable range of degree of staining λ 70 is that 440nm is following, preferred scope is below the 430nm, and the preferable range of degree of staining λ 5 is that 365nm is following, preferred scope is below the 363nm.Spectral transmission in the wave band of λ 70～700nm is shown as more than 70%.

[manufacturing of opticglass]

Opticglass of the present invention can followingly obtain: form in order to obtain target glass, weighing is as the oxide compound of raw material, carbonate, vitriol, nitrate, oxyhydroxide etc. and be in harmonious proportion, thorough mixing is made mix, in melt container internal heating, fusion, and carry out deaeration, stirring, make homogeneous and do not contain the melten glass of bubble, and, obtain opticglass of the present invention this melten glass moulding.Specifically, can use known scorification to make.

[precise compression molding with pre-type body]

Then precise compression molding of the present invention is described with pre-type body.

Precise compression molding of the present invention is characterised in that with pre-type body its opticglass by the invention described above forms.Above-mentioned precise compression molding is the glass block of confession under directions in precise compression molding with pre-type body (hereinafter referred to as pre-type body), and it is the glass forming body suitable with the quality of precise compression molding product.

Below, pre-type body is elaborated.Pre-type body is meant that the heating back supplies in the glass preform of precise compression molding, be also referred to as the moulding of mould optics as everyone knows at this precise compression molding, be meant that the molding surface by transfer printing (transferring) compression molding mould forms the method for the optical function face of optical element.Need to prove that the optical function face is meant the face of the refraction of light, reflection, diffraction or the incident/outgoing that make in the optical element as controlled member, the lens face in the lens etc. is equivalent to this optical function face.

During precise compression molding in order to prevent reaction, the fusion of glass and compression molding mould molding face, simultaneously for glass is extended well along molding surface, preferably in the surface-coated mold release film of pre-type body.As the kind of mold release film, can enumerate precious metal (platinum, platinum alloy), oxide compound (oxide compound of Si, Al, Zr, La, Y etc.), nitride (nitride of B, Si, Al etc.), contain carbon film.

As containing carbon film, preferably be the film (when representing constituent content in the film with atom %, the content of carbon is more than the content of other elements) of main component with carbon.Specifically, can the illustration carbon film, hydrocarbon film etc.As the one-tenth embrane method that contains carbon film, utilize following method to get final product: the known method such as vacuum vapour deposition, sputtering method, ion plating method of having used the carbon raw material; The known method such as thermolysis of material gas such as hydrocarbon have been used.For other films, can use film forming such as vapour deposition method, sputtering method, ion plating method, sol-gel method.

Pre-type body is made via following operation: melten glass is made in frit heating, fusion, and with above-mentioned melten glass moulding.

It is following method that the 1st of pre-type body is made example: the fused glass block that is separated predetermined weight by melten glass also cools off, and it is shaped to the pre-type body that equates with this fused glass block quality.For example, with the frit fusion, clarify, homogenize and prepare the melten glass of homogeneous, flow out from adjusting mass flowing nozzle or the outlet pipe that platinum after the temperature or platinum alloy make.Under the situation of small-sized pre-type body of moulding or the pre-type body of globular, the form of dripping with the melten glass of desired quality drips melten glass from mass flowing nozzle, and it is caught by the pre-body formed mould of type, is shaped to pre-type body.Perhaps, the melten glass of same desired quality is dripped from mass flowing nozzle be added drop-wise to liquid nitrogen etc., pre-type is body formed.Under the situation of on the make large-scale pre-type body, flow down molten glass flow from outlet pipe, catch the leading section of molten glass flow with the body formed mould of pre-type, at the nozzle of molten glass flow with after forming the necking section between the body formed mould of type in advance, make the body formed mould of pre-type under descend rapidly, the surface tension of utilizing melten glass, receives the fused glass block of desired quality, thereby is shaped to pre-type body from molten glass flow in neck down portions on receiving-member.

Have indefectible, dirt in order to make, the smooth surface of fold, surface deformation etc., the pre-type body of for example free surface, can use following method etc.: on the pre-body formed mould of type etc. fused glass block being applied blast and makes its situation compacted under that floats is pre-type body; Perhaps make it form liquid material cooling under normal temperature, normal pressure such as liquid nitrogen, in resulting medium, add melten glass and drip, be shaped to pre-type body for gas.

When the situation compacted under that fused glass block is floated is pre-type body, apply blast upwards to fused glass block jet flow stream (be called and float gas).At this moment, if the viscosity of fused glass block is low excessively, then floats gas and enter in the glass, the formation bubble also remains in the pre-type body.But,, float gas and can not enter in the glass, but glass block is floated by regulating viscosity to the 3～60dPas of fused glass block.

As the gas that when gas is floated in pre-type body injection, uses, can enumerate air, N ₂Gas, O ₂Gas, Ar gas, He gas, water vapour etc.In addition, blast is not particularly limited, and does not contact with solids such as forming mould surfaces as long as pre-type body is floated.

The precise compression molding product of being made by preform (for example optical element) are most as lens to have a rotation axes of symmetry, and the shape of therefore pre-type body also is preferably the shape with rotation axes of symmetry.As object lesson, ball can be shown or have the shape of a rotation axes of symmetry.As shape with a rotation axes of symmetry, can enumerate: in the shape that comprises the smooth contoured line that has no corner angle or depression on the cross section of above-mentioned rotation axes of symmetry, for example on above-mentioned cross section with minor axis and the corresponding to ellipse of rotation axes of symmetry as the shape of skeletal lines etc., can also enumerate shape after ball flattened (determine one by the axle of ball center and on this direction of principal axis the shape of minification); The face that the face that comprises an intersection point in surface and two intersection points of rotation axes of symmetry is concave surface, comprise another intersection point is the shape of convex surface; Each face that comprises above-mentioned two intersection points is shape of concave surface etc.

The 2nd of pre-type body is made example: be poured into the melten glass of homogeneous in the mold and moulding after, remove the distortion of formed body by annealing, by cutting off or cutting off formed body to be divided into predetermined size, shape, make 2 with upper glass plate, sheet glass is ground, make its smooth surface, and make the pre-type body that the glass by predetermined quality forms.Same preferably also the lining on the surface of the pre-type body of so making contains carbon film and uses.

[optical element]

Then optical element of the present invention is described.Optical element of the present invention is characterised in that its opticglass by the invention described above forms.Specifically, can lens, the prism of lens such as non-spherical lens, spherical lens or plano-concave lens, plano-convex lens, biconcave lens, biconvex lens, male bend moon-shaped lens, recessed meniscus shaped lens, microlens, lens arra, band diffraction grating, the prism of band lens function etc. be shown example.Also can antireflection film be set on the surface as required or have partial reflection film of wavelength selectivity etc.

Optical element of the present invention forms than little glass high dispersion property and local the dispersion by having, thus by with the optical element combination that forms by other glass, can carry out the high order chromatic aberration correction.In addition, optical element of the present invention is formed by the high glass of specific refractory power, therefore can make the optical system miniaturization by being used for image pickup optical system, projection optical system etc.

[manufacture method of optical element]

Then the manufacture method to optical element of the present invention describes.

The manufacture method of optical element of the present invention is characterised in that it possesses following operation: the precise compression molding of the invention described above is heated with pre-type body, use the compression molding mould to carry out precise compression molding.

For the oxidation of the molding surface that prevents the compression molding mould or the mold release film that on above-mentioned molding surface, is provided with, preferably in the non-oxidizing gas atmosphere such as mixed gas of nitrogen or nitrogen and hydrogen, carry out the heating and the mold pressing procedure of compression molding mould and pre-type body.In non-oxidizing gas atmosphere, the pre-type that is covered surface to contain carbon film also not oxidized, thereby above-mentioned film remains on the surface of the moulding product behind the precise compression molding.This film finally should be removed, and in order to contain carbon film than being easier to and removing fully, can heat the precise compression molding product in oxidizing atmosphere, for example air.Contain carbon film oxidation, remove and should under the temperature that the precise compression molding product can not be out of shape because of heating, carry out.Specifically, preferably in being lower than the temperature range of second-order transition temperature, carry out.

Use the compression molding mould in advance molding surface is processed into accurately desired shape in the precise compression molding, but the fusion of glass when preventing mold pressing also can form mold release film on molding surface.As mold release film, can enumerate and contain carbon film, nitride film, noble metal film, as containing carbon film, be preferably hydrogenation carbon film, carbon film etc.In the precise compression molding, the shape that pre-type body is supplied to molding surface is through between precision machined a pair of mold respect to one another and the bed die, and the two is heated to and 10 with forming mould and pre-type body then ⁵～10 ⁹The temperature of the glass viscosity correspondence of dPas is with softening pre-type body, and it is carried out extrusion forming, and the molding surface with forming mould critically is transferred on glass thus.

In addition, between the shape of molding surface is through precision machined a pair of mold respect to one another and bed die, supply with and be warmed up in advance and 10 ⁴～10 ⁸The pre-type body of the temperature of the glass viscosity correspondence of dPas carries out extrusion forming to it, can critically be transferred to the molding surface of forming mould on glass thus.

Pressure during pressurization and time can be considered the viscosity of glass etc. and suitably decision, and for example, molding pressure can be about 5～15MPa, and clamp time can be 10～300 seconds.

Mold pressing parameter such as clamp time, molding pressure can suitably be set in known scope according to the shape of moulding product, size.

Afterwards, forming mould and precise compression molding product are cooled off, preferably open mould after the temperature below being cooled to strain point, take out the precise compression molding product.Need to prove,, can suitably adjust the anneal condition of the moulding product in when cooling, for example annealing speed etc. in order critically to reach the expected value of optical characteristics.

The manufacture method of above-mentioned optical element can roughly be divided into following 2 kinds of methods.In the method 1, the preformed parison is imported in the compression molding mould, this forming mould and glass material are heated in the lump, thereby make optical element, when formed precisions such as attention raising surface accuracy, eccentric precision, recommend this method 1.In the method 2,, import in the compression molding mould of preheating and carry out precise compression molding, thereby make optical element, paying attention to recommending when boosting productivity this method 2 heating of pre-type body.

Optical element of the present invention need to prove, even also can be made without the compression molding operation.For example, can obtain by the following method: the melten glass of homogeneous is poured into molds glass block in the mold, anneal and remove distortion, and adjust annealing conditions and adjust optical characteristics so that the specific refractory power of glass reaches desired value, then cut off then or cut off glass block and make sheet glass, and then carry out grinding, grinding and make optical element.

Embodiment

Below, the present invention will be described in more detail by embodiment, but the present invention is not limited by these embodiment.

Embodiment 1

Form in order to obtain the glass shown in the table 2, use as being used to import the raw material of each composition and distinguish corresponding oxide compound, carbonate, vitriol, nitrate, oxyhydroxide etc., raw materials weighing and thorough mixing become mixing raw material (mixedbatch), this mixing raw material is put in the platinum alloy crucible, and heating, fusion.After the fusion, melten glass is poured in the mold, and naturally cools near the second-order transition temperature, put into annealing furnace then immediately, anneal naturally cools to room temperature after about 1 hour in stove in glass transition temperature range, thereby obtains opticglass No.1～No.78.

Table 2

The crystallization that does not have the enough microscopic examinations of energy to arrive in the resulting opticglass.

The various characteristics of the opticglass that so obtains is shown in table 2.

Need to prove that the various characteristics of opticglass is measured by method shown below.

(1) refractive index n d, ng, nF, nc and Abb vd

Refractive index n d, ng, nF, nc, the Abb vd of the glass that obtains with cooling rate-30 ℃/hour cooling have been measured by the refractometry of Japanese optics nitre industry meeting standard.

(2) liquidus temperature LT

Put into glass in the stove that is heated to preset temperature and kept 2 hours, the observation by light microscope glass inside of cooling back by 100 times is according to having or not crystallization to determine liquidus temperature.

(3) glass transition temperature Tg

Utilize differential scanning calorimeter (DSC) to measure for 10 ℃/minute with heat-up rate.

(4) part disperses than Pg, F

Calculate by refractive index n g, nF, nc.

(5) local ratio and normolineal deviation delta Pg, the F of disperseing

By disperseing than Pg according to the part, the part on the normal line that F and Abb vd calculate disperses than Pg, F ⁽⁰⁾Calculate.

(6) proportion

Measure according to Archimedes's method.

(7)λ80、λ70、λ5

The having of used thickness 10mm is parallel to each other and through the planar glass specimen of optical grinding, measures the spectral transmission in the wave band of wavelength 280nm to 700nm.At the light of incident intensity A vertically through a plane of optical grinding, measure from the intensity B of the light of another plane outgoing, calculate spectral transmission according to B/A.Therefore, also comprise the reflection loss of the light of specimen surface in the spectral transmission.Spectral transmission is that the wavelength of 80% sample is that λ 80, spectral transmission are that the wavelength of 70% sample is that λ 70, spectral transmission are that the wavelength of 5% sample is λ 5.

Comparative example

Composition for the embodiment 40 of the document 5 that patents utilizes the method for putting down in writing in the document that glass is fused.Its result, in fusion with the state devitrification of glass melt.The photo of the material of devitrification is seen Fig. 1.

Embodiment 2

For each opticglass that obtains in embodiment 1, to make, with the fusion of blended frit, clarify, homogenize and make melten glass, dripping melten glass from the nozzle of platinum manufacturing drips and catches with the body formed mould of pre-type, apply blast and make under its situation of floating, be shaped to the pre-type body of the globular that forms by above-mentioned various glass.

In addition, flow out above-mentioned melten glass continuously from the platinum tubulation, catch its bottom with the body formed mould of pre-type, after in molten glass flow, making the necking section, make the body formed mould of pre-type under descend rapidly, cut off molten glass flow in the necking section, on the pre-body formed mould of type, catch isolating fused glass block, make the pre-type body of its situation compacted under that floats then applying blast for forming by above-mentioned various glass.

Resulting pre-type body is the high-quality pre-type body of homogeneous on the optics.

Embodiment 3

The melten glass that flows out continuously preparation among the embodiment 2 also is poured in the mold, anneals after being shaped to glass block, and cuts off, thereby obtain the sheet glass more than 2.These sheet glass are carried out grinding, grinding, make the pre-type body that forms by above-mentioned various glass.

Embodiment 4

The surface coated of the pre-type body of making in embodiment 2,3 contains carbon film, this pre-type body imported to be included in be provided with on the molding surface in the compression molding mould that carbon is the SiC of mold release film mold, bed die and the mould made, in nitrogen atmosphere in the lump hot briquetting mould and pre-type body with softening pre-type body, carry out precise compression molding, make various lens such as the aspheric surface male bend moon-shaped lens that forms by above-mentioned various glass, the recessed meniscus shaped lens of aspheric surface, aspheric surface biconvex lens, aspheric surface biconcave lens thus.Need to prove that each condition of precise compression molding is adjusted in above-mentioned scope.

Various lens to making like this are observed, and the result does not confirm gonorrhoea that phase-splitting produces etc., and lens surface does not confirm scar, smudgy, damaged fully.

Repeat such technology and carry out the volume production test of various lens, the unfavorable conditions such as fusion of glass and compression molding mould do not take place, can produce the surface accurately and be high-quality lens with inside.Also can be coated with antireflection film on the surface of the lens that so obtain.

Next, heat, soften being coated with the above-mentioned pre-type body that contains carbon film, this pre-type body is imported in the compression molding mould of preheating separately, carry out precise compression molding, make various lens such as the aspheric surface male bend moon-shaped lens that forms by above-mentioned various glass, the recessed meniscus shaped lens of aspheric surface, two two convex lens of non-ball, aspheric surface biconcave lens thus.Need to prove that each condition of precise compression molding is adjusted in above-mentioned scope.Various lens to making like this are observed, and the result does not confirm gonorrhoea that phase-splitting produces etc., and lens surface does not confirm scar, smudgy, damaged fully.

The shape of the molding surface of all right appropriate change compression molding mould, thus various optical elements such as prism, microlens, lens arra made.

Embodiment 5

Use each lens of making among the embodiment 4, made the various replacement lens of the Single-sens reflex camera that is used for built-in each lens.

And then use each lens of making among the embodiment 4, make the various optical systems of small digital cameras, and carried out modularization.And, also image sensors such as CCD or CMOS are installed in and have carried out modularization in these optical systems.

By using the various lens of in embodiment 4, making by this way, can access high function, small-sized optical system, replace lens, lens module, camera head.Make up with the lens of Spectralite with high refractivity and low dispersion manufacturing by the lens of will be among the embodiment 4 making, can access various optical systems of carrying out high order chromatic aberration correction (correction ofhigh-order chromatic aberration) and the camera head that possesses this optical system.

Industrial applicibility

Opticglass of the present invention has devitrification resistance, the lower glass transition temperatures of the high dispersion property of high refractive index, excellence, and is suitable for precise compression molding.In addition, this opticglass is suitable for the high order chromatic aberration correction, is suitable for making precise compression molding with pre-type body, optical element.

Claims

1. opticglass, it is an oxide glass, when representing with positively charged ion %, it contains:

15%～35% Si ⁴⁺,

0%～20% B ³⁺,

15%～25% Nb ⁵⁺,

0%～9% Ti ⁴⁺,

0%～3% Zr ⁴⁺,

0.25%～2.5% W ⁶⁺,

0%～19% Li ⁺,

3%～19% Na ⁺,

0%～18% K ⁺,

0%～9% Zn ²⁺,

0%～2% Ba ²⁺,

0%～3% Ca ²⁺,

Nb ⁵⁺Content with respect to Nb ⁵⁺And Ti ⁴⁺The cation ratio Nb of total content ⁵⁺/ (Nb ⁵⁺+ Ti ⁴⁺) be 0.71～1 scope,

With Si ⁴⁺Measure and Nb for 20 times of content ⁵⁺The total 20Si of 2 times of amounts of content ⁴⁺+ 2Nb ⁵⁺Be made as H, with B ³⁺8 times of amounts of content, Li ⁺6 times of amounts of content, Na ⁺5 times of amounts of content, K ⁺3 times of amounts of content, Zn ⁺Measure and W for 3 times of content ⁶⁺The total 8B of 7 times of amounts of content ³⁺+ 6Li ⁺+ 5Na ⁺+ 3K ⁺+ 3Zn ²⁺+ 7W ⁶⁺When being made as L, H/L is 1.15～2.55 scope,

Ti ⁴⁺, Nb ⁵⁺And Zr ⁴⁺Total content be 20%～30.78% scope,

Ba ²⁺, Ca ²⁺And Zr ⁴⁺Total content be 0%～3.79% scope,

Refractive index n d is 1.75～1.86 scope,

Abb vd is 24～30 scope.

2. opticglass as claimed in claim 1, wherein, second-order transition temperature is 480 ℃～535 ℃ a scope.

3. opticglass as claimed in claim 1 or 2, wherein, liquidus temperature is 1000 ℃～1060 ℃ a scope.

4. as each described opticglass of claim 1～3, wherein, the local dispersion than Pg, F is 0.57～0.62.

5. as each described opticglass of claim 1～4, wherein, Si ⁴⁺And B ³⁺Total content be 20%～50%.

6. as each described opticglass of claim 1～5, wherein, Sr ²⁺Content be 0%～2% scope.

7. as each described opticglass of claim 1～6, wherein, Ba ²⁺And Ca ²⁺Total content be 0%～3% scope.

8. as each described opticglass of claim 1～7, wherein, Li ⁺, Na ⁺And K ⁺Total content be 25%～45% scope.

9. a precise compression molding is with pre-type body, and its each described opticglass by claim 1～8 forms.

10. a precise compression molding is with the manufacture method of pre-type body, and described manufacture method is made the described pre-type body of claim 9 via following operation: melten glass is made in frit heating, fusion, and made described melten glass moulding.

11. an optical element, its each described opticglass by claim 1～8 forms.

12. the manufacture method of an optical element, described manufacture method possesses following operation: the described precise compression molding of claim 9 is heated with pre-type body, use the compression molding mould to carry out precise compression molding.

13. the manufacture method of optical element as claimed in claim 12 wherein, heats precise compression molding with pre-type body and compression molding mould in the lump, carries out precise compression molding.

14. the manufacture method of optical element as claimed in claim 12 wherein, after the heating precise compression molding is with pre-type body, imports in the compression molding mould after the preheating, carries out precise compression molding.

15. a camera head, it possesses the described optical element of claim 11.